I mainly use GarageBand for recording and even mastering, but I ran across some great mastering software from IK Multimedia called the Lurssen Mastering Console. It comes as desktop software and will also install as a plug-in automatically. It's only $59.99 right now and is usually $159.99. ( https://www.ikmultimedia.com/products/lurssen/index.php?p=versions#view )
I just finished playing with it after a couple of hours, re-mastering a couple of songs, and I have to say that the difference it makes is pretty immense. My vocals are much more clear.
The way I used it was that I output my EQ'd mix to a WAV file (44.1K/24-bit), then loaded that file into Lurssen. Chose a preset (for both songs I used Pop / Brighter), then used the automation feature to automate input gain and EQ "push." Once I was satisfied, I exported the song back out to a WAV, then loaded it into a GarageBand project that I used for mastering. Then I applied a Direction Mixer, Multipressor and Limiter. The results are fantastic.
I found a video on YouTube about this. The thing that blew my mind was when they used the app to listen in the car and make adjustments right there and then on their tablet! Very cool.
I use Izotope's Ozone, which takes a similar approach with presets that you can then just adjust to taste. I only have the Elements version, which is limited, but then so am I, so it's probably about right for me!
I may or may not be an enigma
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Yeah, that car scene really impressed me. But I did find that's on the be-all, end-all as far as mastering, which is why I described my workflow above. For adding that bit of color, it's awesome!